Waste collection and disposal process

ABSTRACT

A process is disclosed for collecting and disposing of waste (1), in particular household rubbish. Waste is separately collected and sorted at the place at which it is produced in plastic bags (3a, 3b, 3c) provided with appropriate distinguishing markings (2a, 2b, 2c) in accordance with recycling criteria. Portions of waste (4) are packaged by closing and vacuum-sealing the plastic bags, and the closed and vacuum-sealed bags that contain the various types of waste are placed together at random into at least one common garbage container (5) and transported to a central collecting point where the plastic bags are sorted according to their markings for final disposal and/or recycling.

The invention concerns a method for collecting and disposing of wastes,in particular household wastes, in which the waste is collectedseparately, on the basis of material recycling criteria, in plastic-filmreceptacles which can be distinguished from one another by correspondingmarkings, and the plastic-film receptacles are taken to a centralcollection point for final storage and/or further use and there sortedaccording to their markings.

New laws and ordinances concerning the avoidance, reduction,reprocessing, and reutilization of garbage demand frugal use ofpackaging material, utilization of reusable packaging, and especiallyappropriate sorting, for recycling, of wastes which are produced. Forthis reason, there have already existed for some time containers, set upcentrally by communities, into which end users can dump their wastepaper and used glass.

Garbage sorting also takes place in households, a three-part separationinto organic wastes, plastics, and other wastes usually being performed.Although this garbage separation contributes to savings in reusablematerials, it entails problems with regard to "garbage hygiene." Inother words, the distribution of garbage into different bins greatlyincreases the residence time of the garbage in the household, since theindividual bins containing wastes of various kinds are emptied only atrelatively long intervals. With organic garbage in particular, it hasbeen found that storage of food residues in organic waste bins can lead,after only a few days, to contamination with spores, bacteria, maggots,etc. In addition, unpleasant odors can develop relatively quickly.

Furthermore, garbage separation as usually performed today also requiresspecial garbage transport vehicles with chambers, separated from oneanother, for the various wastes, is such a way that must each be capableof being loaded with garbage and individually emptied. Garbage transportvehicles are accordingly of relatively complex configuration, and thusexpensive. Alternatively, the bins containing the various kinds ofgarbage can also be picked up separately. This is, however, also complexand therefore expensive.

To eliminate this problem, it is proposed in EP-A-0 537 771 that thedifferent garbage fractions be collected in correspondingly markedgarbage bags, and the garbage bags be disposed of together with thegarbage. The result of this feature is that the various garbagefractions can be carried off in a garbage vehicle but the latter doesnot need to be equipped with separate chambers, since the garbagefractions can easily be separated once again on the basis of themarkings of the garbage bags when the garbage vehicle is unloaded.Problems nevertheless still occur with regard to garbage hygiene, sincethe individual garbage bags containing different types of waste areemptied only at relatively long time intervals.

It is therefore the object of the invention to configure a method of thekind cited initially for collecting and disposing of household wastes insuch a way that, while retaining the requisite garbage separation,hygienic and less complex collection and disposal of household wastes ispossible.

This object is substantially achieved, according to the invention, bythe fact that:

a) the waste is packaged in portions, at the place where it is produced,by the fact that a plastic-film receptacle for the waste is produced, inthe respective desired size, from a tubular film; and after filling, theplastic-film receptacles are heat-sealed and vacuum-packed; and

b) the heat-sealed and vacuum-packed plastic-film receptacles containingthe various kinds of waste are temporarily stored, unsorted, in at leastone common collection vessel before being taken, also unsorted, to thecentral collection point.

While with the known method the garbage is collected in relatively largegarbage bags, which in single-family houses are generally located in thegarage and in multi-family houses are provided at a central garbagecollection point, and are sealed only in order to be carried off to thegarbage dump, according to the invention provision is made for the wasteto be packaged at the place where it is produced, i.e. directly inhouseholds, by heat-sealing and vacuum-packing the plastic-filmreceptacles. What is essential here is that the waste is packaged inportions, i.e. in small quantities, so that the plastic-film receptaclesremain open for only a minimal time, thus ensuring that contamination byspores, bacteria, maggots, etc., or unpleasant odors, cannot occur. Thevolume of wastes to be collected is also reduced, so that the garbagebins made available can be comparatively small.

The plastic-film receptacles are hermetically sealed as a result ofheat-sealing and vacuum-packing, as is known per se from printeddocuments U.S. Pat. No. 5,027,578, U.S. Pat. No. 5,425,456, U.S. Pat.No. 4,044,524, and Patent Abstracts of Japan, Vol. 18, No. 483 (M-1670),Sep. 8, 1994, but only for the heat-sealing of plastic-film receptaclesin standard sizes. In contrast thereto, according to the invention theplastic-film receptacles are produced from the tubular film in therespective size that is desired or required, so that almost no scrapresults.

Packaging the waste in portions under vacuum yields the additionaladvantage that the individual small garbage units are very manageableand stable, which simplifies their handling. It has been found, inparticular, that there is very little tendency for the plastic-filmreceptacles to tear, which can happen much more often with large,heavily packed garbage sacks.

Lastly, packaging of the waste in portions directly in households hasthe advantage that the heat-sealed and vacuum-packed plastic-filmreceptacles containing the various kinds of waste can easily be storedtemporarily, unsorted, in a common collection vessel, before beingtaken, also unsorted, to the central collection point.

Because the household wastes are vacuum-packed in portions at the pointwhere they are produced, i.e. in households, there is also no danger ofcontamination by spores, bacteria, maggots, etc., so that waste hygieneis perfect.

Vacuum-packing also contributes to a reduction in the volume of thewastes being collected, so that the garbage bins can be madecomparatively small and the bins need to be emptied less often.

Particularly good garbage hygiene is achieved if multiple portions ofwaste are collected in each of the plastic-film receptacles and eachportion is individually packaged by heat-sealing and vacuum-packing.This makes it possible to package the garbage under vacuum directlyafter it is produced without thereby wasting packaging material.

According to a preferred embodiment, a tubular film which is open atboth of its axial ends is used to form the plastic-film receptacles, theone open end being closed in particular by means of a heat-sealingprocedure, and waste being introduced through the end which is stillopen. The use of tubular films makes it possible to produce plastic-filmreceptacles in the particular desired size and without substantialscrap, by closing the filled portion of the tubular film and cutting itoff from the tubular film to the appropriate length.

The waste introduced into the tubular film is packaged, according to afurther embodiment of the invention, by closing off the filled portionof the tubular film by means of a first heat-sealing operation, forminga first heat-sealed seam; withdrawing the air from the filled portion ofthe tubular film by means of, in particular, a vacuum pump or anextractor fan and completing the vacuum by means of a secondheat-sealing operation, forming a second heat-sealed seam which liesbetween the first heat-sealed seam and the waste; and lastly detachingthe sealed plastic-film receptacle. Packaging of the waste introducedinto the tubular film by forming two parallel heat-sealed seams has theadvantage that the first heat-sealed seam, which is produced beforeevacuation of the plastic-film receptacle, can simultaneously form thebottom of the next plastic-film receptacle when the plastic-filmreceptacle is separated at a suitable point from the tubular film, sothat handling is easy. The second heat-sealed seam, by means of whichthe evacuated plastic-film receptacle is sealed, can be configured, forexample, as a defined break point, and for that purpose can beconfigured with differing thickness in its longitudinal direction.

Regarding further advantageous embodiments of the method according tothe invention, reference is made to the dependent claims and to thedescription below of an exemplifying embodiment with reference to thedrawings, in which:

FIG. 1 shows, in a schematic view, the individual steps which areperformed in the method as defined in the present invention; and

FIG. 2 shows, in a sectioned view, a heat-sealing and vacuum-packingdevice that is used to carry out the method depicted in FIG. 1.

In the method according to the invention for collecting and disposing ofhousehold wastes, waste 1 is separated according to materials recyclingcriteria, and the individual types of garbage--such as organic garbage,plastics, and other garbage-are collected separately from one another inplastic-film receptacles 3a, 3b, 3c which can be distinguished from oneanother by corresponding markings 2a, 2b, 2c. Markings 2a, 2b, 2c can beof different kinds. For example, symbols for the substances for whichthey are intended can be provided as markings 2a, 2b, 2c. Alternatively,it is also possible, in known fashion, to select different colors forplastic-film receptacles 3a, 3b, 3c.

In the present case, what is used as plastic-film receptacles 3a, 3b, 3care tubular films made of biodegradable material, which are each rolledup in the manner of a condom to form an annular bead 7 at the top andcan be pulled off downward from annular bead 7, the open lower end ofthe portion of the tubular film hanging down from annular bead 7 beingsealed by means of a heat-sealing operation in order to form pouch-likeplastic-film receptacles 3a, 3b, 3c. Annular bead 7 defines an opening 8through which plastic-film receptacles 3a, 3b, 3c can be filled withwaste 1.

When plastic-film receptacles 3a, 3b, 3c are sufficiently filled withwaste 1 (the particular quantity being determined according to theuser's wishes), waste 1 is heat-sealed under vacuum by means of aheat-sealing and vacuum-packing device 4. In this context, it ispossible to collect several small portions of waste in each plastic-filmreceptacle and individually package each portion by heat-sealing andvacuum-packing.

Plastic-film receptacles 3a, 3b, 3c, thereby sealed in air-tight fashionand containing different wastes, are then temporarily stored together,unsorted, in a collection vessel 5, for example a garbage bin, and takenby conventional garbage transport vehicles 6 to a garbage dump. Thereplastic-film receptacles 3a, 3b, 3c are sorted again on the basis oftheir contents, either manually or automatically, and sent on forfurther processing.

With this method, the various household wastes are thus collectedseparately from one another, but stored temporarily and transported to agarbage dump together, and only there separated from one another forfinal processing. Only one garbage bin therefore needs to be present ineach household, and garbage transport vehicles 6 also do not need to bespecially configured in order to be able to carry off the various kindsof waste.

In addition, it is possible to equip the plastic-film receptacles with acode to identify the consumer and/or the contents of the plastic-filmreceptacles, so that it is possible to determine garbage disposal costsin accordance with actual use.

Coding is preferably accomplished by means of a correspondingconfiguration of the heat-sealed seams on the plastic-film receptacles.For example, an electrical light radiator can be used to produce theheat-sealed seams, with which it is possible to configure heat-sealedseams of differing thicknesses over their length, in the manner of abarcode.

FIG. 2 depicts an embodiment of a heat-sealing and vacuum-packing device4 as is used to seal plastic-film receptacles 3a, 3b, 3c with the methodexplained above. Device 4 comprises two heat-sealing units 9, 10arranged one above another, and a vacuum-packing apparatus 11 providedbetween heat-sealing units 9, 10. Heat-sealing units 9, 10 each comprisea stationary heat-sealing jaw 9a, 10a on which a heating wire 15 isprovided, and a movable heat-sealing jaw 9b, 10b that can be pressedsubstantially horizontally against stationary heat-sealing jaw 9a, 10a,the tubular film being in each case passed through between heat-sealingjaws 9a, 9b; 10a, 10b of heat-sealing units 9, 10.

Vacuum-packing apparatus 11 consists of a closed duct 12, extending overthe entire width of the tubular film, over whose length a plurality ofsuction openings 13 are provided. Suction openings 13 each have asharp-edged collar 14 which makes it possible to penetrate into thetubular film in order to pull a vacuum therein. Collars 14 can beheatable in order to burn holes into the film and thereby facilitate theinsertion of collars 14 into plastic-film receptacle 3a.

To seal and vacuum-pack a plastic-film receptacle 3a, first upperheat-sealing unit 9 is actuated, causing plastic-film receptacle 3a tobe sealed by forming a first heat-sealed seam. Then vacuum-packingapparatus 11 is actuated, and air is sucked out of the enclosed duct 12,causing the tubular film to be drawn against sharp-edged collars 14 sothat the latter penetrate into the tubular film and create a vacuum inthe interior of plastic-film receptacle 3a.

Lower heat-sealing unit 10 is then actuated in order to seal theevacuated plastic-film receptacle below the holes created by sharp-edgedcollars 14, and simultaneously detach it from the tubular film.

Lastly, heat-sealing jaws 9a, 9b, 10a, 10b of heat-sealing units 9, 10are moved apart again so that additional tubular film can be pulled offdownward from annular bead 7 for a new plastic-film receptacle. In theprocess, the first heat-sealed seam, which was produced in the previoussealing and evacuation procedure to seal the plastic-film receptacle,forms the bottom of the next plastic-film receptacle.

What is claimed is:
 1. A method for collecting and disposing of wastes,in which the waste (1) is collected separately, on the basis of materialrecycling criteria, in plastic-film receptacles (3a, 3b, 3c) which canbe distinguished from one another by corresponding markings (2a, 2b,2c), and the plastic-film receptacles (3a, 3b, 3c) are taken to acentral collection point for final storage or further use and theresorted according to their markings (2a, 2b, 2c), wherein said methodcomprises the steps of:a) packaging the waste in portions at the placewhere it is produced, by:producing, from a tubular film, a plastic-filmreceptacle (3a, 3b, 3c) for each portion of the waste in such a way thateach plastic-film receptacle (3a, 3b 3c) has a variable size thatdepends upon the variable size of a respective one of said portions,filling each plastic-film receptacle (3a, 3b, 3c) with said respectiveone of said portions, and heat-sealing and vacuum-packing theplastic-film receptacles (3a, 3b, 3c) after filling; and b) temporarilystoring, in an unsorted manner the heat-sealed and vacuum-packedplastic-film receptacles (3a, 3b, 3c) containing the various kinds ofwaste, in at least one common collection vessel (5) before taking suchheat-sealed and vacuum-packed plastic-film receptacles (3a, 3b, 3c),also unsorted, to the central collection point.
 2. The method as definedin claim 1, wherein multiple portions of waste (1) are collected in eachof the plastic-film receptacles (3a, 3b, 3c) and each portion isindividually packaged by heat-sealing and vacuum-packing.
 3. The methodas defined in claim 1, wherein the plastic-film receptacles (3a, 3b, 3c)are produced from a tubular film made of biodegradable plastic.
 4. Themethod as defined in claim 1, wherein for packaging of the waste (1)introduced into the tubular film, the filled portion of the tubular filmis sealed by means of a first heat-sealing operation, forming a firstheat-sealed seam; the air is withdrawn from the filled portion of thetubular film by means of, in particular, a vacuum pump (11) or anextractor fan and the vacuum is completed by means of a secondheat-sealing operation, forming a second heat-sealed seam which liesbetween the first heat-sealed seam and the waste (1); and the sealedplastic-film receptacle (3a, 3b, 3c) is detached from the tubular film.5. The method as defined in claim 4, wherein for vacuum-packing, holesare punched or burned into the sealed plastic-film receptacle (3a, 3b,3c), and the air is withdrawn from the plastic-film receptacle (3a, 3b,3c) through said holes; and the second heat-sealed seam is applied tothe plastic-film receptacle (3a, 3b, 3c) between the holes and the waste(1).
 6. The method as defined in claim 5, wherein detachment occurs atthe second heat-sealed seam, and for that purpose the second heat-sealedseam is configured with differing thickness in its longitudinaldirection, forming a defined break point.
 7. The method as defined inclaim 4, wherein an electrical light radiator is used as theheat-sealing device at least for producing the second heat-sealed seam.8. The method as defined in claim 1, wherein the plastic-filmreceptacles (3a, 3b, 3c) are equipped, in particular during theheat-sealing and vacuum-packing operation, with a code to identify theconsumer.
 9. The method as defined in claim 8, wherein coding takesplace by means of suitable configuration of the heat-sealed seam on theupper side and/or the lower side of the plastic-film receptacles (3a,3b, 3c).
 10. The method as defined in claim 1, wherein plastic-filmreceptacles (3a, 3b, 3c) which have different colors in order toidentify their contents are used.
 11. The method as defined in claim 1,wherein the plastic-film receptacles are each equipped, in order toidentify their contents, with symbols for the substances for which theyare intended.
 12. The method as defined in claim 1, wherein theheat-sealed and vacuum-packed plastic-film receptacles (3a, 3b, 3c) areweighed before being taken to the central collection point, and a costcalculation is made on the basis of the weight determined.
 13. Themethod as defined in claim 1, wherein the plastic-film receptacles (3a,3b, 3c) are sorted automatically at the central collection point, bydetection of their markings or of a code provided.